Pulmonary ultrasound and pulse oximetry versus chest radiography and arterial blood gas analysis for the diagnosis of acute respiratory distress syndrome: a pilot study

Abstract

IntroductionIn low-resource settings it is not always possible to acquire the information required to diagnose acute respiratory distress syndrome (ARDS). Ultrasound and pulse oximetry, however, may be available in these settings. This study was designed to test whether pulmonary ultrasound and pulse oximetry could be used in place of traditional radiographic and oxygenation evaluation for ARDS.MethodsThis study was a prospective, single-center study in the ICU of Harborview Medical Center, a referral hospital in Seattle, Washington, USA. Bedside pulmonary ultrasound was performed on ICU patients receiving invasive mechanical ventilation. Pulse oximetric oxygen saturation (SpO2), partial pressure of oxygen (PaO2), fraction of inspired oxygen (FiO2), provider diagnoses, and chest radiograph closest to time of ultrasound were recorded or interpreted.ResultsOne hundred and twenty three ultrasound assessments were performed on 77 consecutively enrolled patients with respiratory failure. Oxygenation and radiographic criteria for ARDS were met in 35 assessments. Where SpO2 ≤ 97 %, the Spearman rank correlation coefficient between SpO2/FiO2 and PaO2/FiO2 was 0.83, p < 0.0001. The sensitivity and specificity of the previously reported threshold of SpO2/FiO2 ≤ 315 for PaO2/FiO2 ≤ 300 was 83 % (95 % confidence interval (CI) 68–93), and 50 % (95 % CI 1–99), respectively. Sensitivity and specificity of SpO2/FiO2 ≤ 235 for PaO2/FiO2 ≤ 200 was 70 % (95 % CI 47–87), and 90 % (95 % CI 68–99), respectively. For pulmonary ultrasound assessments interpreted by the study physician, the sensitivity and specificity of ultrasound interstitial syndrome bilaterally and involving at least three lung fields were 80 % (95 % CI 63–92) and 62 % (95 % CI 49–74) for radiographic criteria for ARDS. Combining SpO2/FiO2 with ultrasound to determine oxygenation and radiographic criteria for ARDS, the sensitivity was 83 % (95 % CI 52–98) and specificity was 62 % (95 % CI 38–82). For moderate–severe ARDS criteria (PaO2/FiO2 ≤ 200), sensitivity was 64 % (95 % CI 31–89) and specificity was 86 % (95 % CI 65–97). Excluding repeat assessments and independent interpretation of ultrasound images did not significantly alter the sensitivity measures.ConclusionsPulse oximetry and pulmonary ultrasound may be useful tools to screen for, or rule out, impaired oxygenation or lung abnormalities consistent with ARDS in under-resourced settings where arterial blood gas testing and chest radiography are not readily available.Electronic supplementary materialThe online version of this article (doi:10.1186/s13054-015-0995-5) contains supplementary material, which is available to authorized users.

Is There a Role for Lung Ultrasound During the COVID‐19 Pandemic?

“…The study of these patterns shows very high sensitivity in cases of interstitial and alveolar-interstitial lung diseases, which have a peripheral distribution. Numerous studies on acute respiratory distress syndrome (ARDS) 6 confirm this. Other studies related to the 2009 pandemic influenza A (H1N1) epidemic 7 confirm these hypotheses even in a virally infectious setting.…”

Chest radiography versus lung ultrasound for identification of acute respiratory distress syndrome: a retrospective observational study

“…Apart from a small pilot study [ 11 ] and a recent evaluation of the Kigali Modification [ 12 ], the use of chest radiography versus the use of lung ultrasound for the identification of ARDS has not been systematically studied. It is also unclear how the choice of imaging would affect ARDS identification.…”

Comparison of peripheral venous and arterial blood gas in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD): a meta-analysis

“…It was revealed that venous PCO2 cannot be used to predict arterial PCO2 by applying a 'correction factor. ' Another investigation reported that the VBG might be useful in determining whether venous blood has a low amount of CO2 and high O2 to exclude hypercapnia and hypoxia [20]. Likewise, the systematic review of estimates of differences between VBG and ABG was subject to a high degree of heterogeneity, which might lead to a further bias.…”